Chiller! -- Ranque-Hilsch Vortex Tube

[crandf]

Okay, some of you may have heard of this. The Ranque-Hilsch Vortex Tube -- air goes in, hot and cold air comes out at different outlets. Its like Maxwell's demon in action! I wonder if the higher strength airpumps are enough?

The commercial website exair.com charges US$209 for the smallest complete cooling kit, and US$129 for the smallest tube. Only difference b/w large and small tube seems to be the flowrate of the air at the desired temperature. I estimate the coldest air achievable in singapre is about 0 degree celsius. Should be cold enough right? And then the hot end can be used to cook your breakfast.

Sigh, probably too expensive after including all needed accessories, unless build all yourself, but I lack the tools needed.
Anyone wants to try it?

Nice short description of the Tube
http://www.phys.tue.nl/lt/projects/vortex.html

Exciting commercial description with nice animation of the Tube in action
http://www.exair.com/vortextube/vt_frmain.htm

Pseudo-comprehensible site and diagrams of the Tube
http://www.visi.com/~darus/hilsch/

Comprehensive site on the Tube
http://www.southstreet.freeserve.co.uk/rhvtmatl/

Spare parts list for DIY Tube
http://olbers.kent.edu/alcomed/Sam_N...orahs_vor.html

NUS student's project on the Tube
http://sps.nus.edu.sg/~ongyians/2172.pdf

[tawauboy]

based on information from the links you provided, i doubt you or anyone would like to try this technique out. two inherent characteristic that kills any interest are the requirement of an air compressor capable of about 8 bar (100+psi) and it’s a very noisy system. anyway, if this technique is viable, you would have seen devices working based on this technique in the market. you’ll be better off using a chiller.

[crandf]

Isn't that what mufflers are for? Besides if really use so high pressure,then how to handle the hot end. Maybe moderately cool air is still possible at airpump pressures?

Proof by non-existence is not very convincing to me.

[tawauboy]

[quote:7444d89546="crandf"]if really use so high pressure........
[/quote:7444d89546]

did you read what was in the link you provided?
in the first link, it says "The basis of the vortex tube is cooling by non-isentropic expansion of a high pressure fluid through a nozzle and in a vortex."
and i doubt you can get a vortex by using air pumps.

[crandf]

I simply meant that the optimum pressure is high, but we dun need to go for that optimum. A less optimum cooling may be possible and enough at airpump pressures.
I dun trust one sentence summaries, they usually leave out everthing else.

I have no experience with the high strength airpumps, so I really dun know how strong they can be, thus I speculate.

[crandf]

Great minds think alike.
http://www.halfbakery.com/idea/ultra...0vortex_20tube
Or maybe half-baked minds have smilar ideas

[BFG]

Crandf, you will need air pressure at 7.2 - 7.6 bar of compressed air for the thing to work. The temperature of the compressed air need to be monitored closely to prevent fluctuation. If you planned to use a lower pressure, I doubt it will work because this equipment need that pressure for the reaction to occur. Airpump and compressor are 2 different equipment altogether. Using an airpump to pump air into the cylindrical metal tube won't have any effect. Do you know how strong 1 bar is? The compressor is used to drive air ratchet. I don't know if an airpump can drive an air ratchet. Also, the cost of getting all the equipment necessary to start this project can replace a few set of high end chiller!

[loupgarou]

hmm, and its kind of redundant having a jet of compressed air at 7.2 bar blowing cold air at the top of the aquarium..

[crandf]

Hmmm, the compressed air is the inlet. Outlet is at reduced pressure, and blowing into heat sinks mounted on the glass wall would be better than blowing on the water surface(ie less loss. Conduction, not evaporation needed.) 7.2 bar is not the min requirement, it is what is often industrially used.
This guy diyed a vortex tube for cooling his computer.
http://madnad.com/OVERCLOCK/
Note the 50psi he used, which is 3.4 bar and achived below 0^oC.

Anyway, I'm over my vortex tube craze. because now I'm into peltier systems! I think many aquarium chillers use peltier coolers already, but those complete systems are very ex. A peltier cooler by itself costs very little.
http://www.amtrade.com/computer_fan/...eltier_fan.htm

Chk here for discussion on diying a peltier cooling system for aquariums
http://fins.actwin.com/nanf/month.9907/msg00207.html

[crandf]

http://www.coolworksinc.com/more_about_ipac1.htm
Says that "50W chiller can cool 10 gallons of water 6ºF to 8ºF below ambient air temperature in a standard aquarium. Multiple Aquarium Chillers can be used to achieve higher temperature differentials."

Assuming only heat input is from strong pl lights and only heat output is into chillers and environment, then say around T=31C=87.8F without chillers.
To cool down to T=23C=73.4F, I estimate at least 100W needed for 10g tank. Around US$40 needed for peltier element alone

For 100g tank, assume fans alone cool down to T=27C=80.6F, then maybe then 500W enough to cool to T=23C=73.4F, US$150. Hmmm, power supply can handle or not...

Costs are based on http://www.americool.com/moduleprices.htm . You can find the peltier element without fans etc, cooling capacity of 14.9W costs $14.75, 72W costs US$21.50. Cheaper with large orders. Min order of US$100. Makes me wonder how much the aquarium chiller companies are conning out of hobbyists.
best is http://www.kryothermusa.com/NewProductsHE.htm
peltier cooler 172W for US$31

[BFG]

You can't compare an ice probe to a chiller. 1 is using fan to cool down the water while the chiller uses compressor and refrigerant to cool down the water column fast. Imagine trying to cool down a 3ft with 1 ice probe. It will work non stop to bring down the water temperature to the required level. A chiller will stop when the desired temperature has been reached and will turn on again if the temperature rise by 1 or 2 degrees. Ice probe are mainly used at those drinking fountain. After a min or 2 of water flow, the water will revert back to the normal temperature of the water supply.

Please get your fact correct before making accusation about aquarium chiller conning hobbyist. You are mentioning 2 different technology of water cooling equipment. The ice probe will lose to the chiller hands down, unless you are using multiple iceprobe. Even then the chiller will still out compete the iceprobe in performance.

I am in no way working in the aquarium chiller industry. I too had considered using the iceprobe for my 3ft but the cost of getting 3 of the iceprobe plus the temperature controller can easily get me a Resun chilller.

[crandf]

Duh! Both are using peltier elements. Diff end product maybe but same basic peltier technology. This pertains, of course, only to the info at the links I provided. No doubt there are indeed chillers and iceprobes that work according to your description, but I'm not talking about those.
The link even specifies that no refrigerants and compressors are used for both iceprobe and chiller, its their main selling point. The fan is only to cool off the hot end of the peltier element for both products.

I dun work for peltiers making companies either.

I haven't ever had so much arrows. Maybe I should explain everything out in words instead of just providing links?

Peltier elements - a solidstate thermoeletric device that creates temperature gradients when current is supplied. Fans or watercooling on the hot side will help to dissipate the heat.
The best is http://madnad.com/OVERCLOCK/, where the guy used both vortex tubes AND peltier elements, my hero! I wish he specified where he got his compressed airline though.

[tawauboy]

[quote:2ffc47b1ea="crandf"]
I haven't ever had so much arrows.
[/quote:2ffc47b1ea]
arrows are arrows only if you see them as arrows.
this is a discussion forum so replies are given for your queries. forumers answered your queries to their best abilities based on the info as well as their opinions. these answers may not be what you like but you can choose not to accept them. or do you wish us to answer your queries by saying
1) yeah! the vortex tube is an excellent idea, cooling from compressed air only.
2) yeah! no need for an air compressor, air pump will do.
3) yeah! no product in the market because they do not know how to use the technology.
4) yeah! it's noisy but a muffler will make this solution whisper quiet.

[tawauboy]

[quote:9b3612cb90="crandf"]Makes me wonder how much the aquarium chiller companies are conning out of hobbyists.
[/quote:9b3612cb90]
before you make such generalised statement, think first. these companies are established to make money, not to benefit hobbyist. benefit hobbyist as in making gadgets to make hobbyist life easier.
maybe you find that peltier based aquarium chiller is overpriced by looking at the cost of the peltier elements. the fact is peltier elements are only a part of the chiller. there are other parts such as fans, cold block, heat sinks, control circuitry, casing and etc. each of these parts cost money especially the cold block and heat sinks.

there is a thread on using peltier to cool aquarium in the marine forum, if i remember correctly. you can check out what's posted there. previously, it is not feasible to diy such a system due to unavailable off-the-shelf cold block(heat exchanger). it is available now.

one thing to note on peltier is that the 'hot' side has about 60 deg c differential to the 'cold' side. that means if the 'cold' side is 20 deg c, then the 'hot' side will be about 80 deg c.

you'll have to design a power supply to provide the curent rating required or you can try your luck with pc power supply.

[crandf]

True, I shouldn't expect everyone to agree with me, and I'm perfectly okay with your comments, tawauboy. But standing on the part of the proposer, I'm quite pissed at 2 replies in particular who I feel IMHO joined in the rockthrowing without first getting a clear idea of what I was proposing. It might not mean much to you if you shoot off without understanding, but your comments undermine my credibility and makes other readers less likely to take this thread seriously.

Hmmm, I guess shooting was an overstatement. But though it was only 2 replies, they combined with the general atmosphere on this thread to give me a feeling of being under enemy fire

Anyway back to topic, anyone knows if Peltier elements are sold at Sim lim square. I chked web and saw only yr1999 references to fans on peltier elements linked with Sim lim square. Went by the other day, but also didn't see any peltier available on shelf.
Powersupply wise maybe go with the higher quality PC power supply as stated in those links. Shouldn't exceed $100.
Fans can get those normal ones lah. Heat sink also can use old CPU and graphic cards heat sinks.

And marine section got meh? I search pelter, peltier and peltiers, but nothing turned up. Can you give a general month/year for that thread, thanks?

[tawauboy]

why not start a new thread to discuss peltier based chiller. leave this thread for the vortex.

as for the thread, i don't remember exactly when but it definitely in the marine. may not be a discussion on diy peltier based chiller, can't remember.

[BFG]

[quote:ef25d95b0d="crandf"]True, I shouldn't expect everyone to agree with me, and I'm perfectly okay with your comments, tawauboy. But standing on the part of the proposer, I'm quite pissed at 2 replies in particular who I feel IMHO joined in the rockthrowing without first getting a clear idea of what I was proposing. It might not mean much to you if you shoot off without understanding, but your comments undermine my credibility and makes other readers less likely to take this thread seriously.

Hmmm, I guess shooting was an overstatement. But though it was only 2 replies, they combined with the general atmosphere on this thread to give me a feeling of being under enemy fire[/quote:ef25d95b0d]

Whoa there bro, rockthrowing? I've read the link that you had provided and IMHO, it is impractical that's why I've posted the reply. Your 1st idea was to use the cold end to cool the tank while the hot end would be used to cook breakfast. er, is that practical? Who would start the contraption in your house should he/she would want to cook a meal? It would take time to tune the system 1st then you could use the end product for cooking as well as cooling your tank. By the time the system is started and has stabilised, your food would have been cooked using the conventional gas cooker.

On my 1st reply that i've posted, the requirement of the 7.2-7.6 bar of compressed air. Do you have personally experienced the strength of that pressure? The 3-tonner tyre is supported by pressure of ard 5 bar if I'm not wrong. An NS serviceman was killed when he tried to replace this vehicle tyre during a puncture! It is VERY DANGEROUS having this kind of pressurised tank in a home. I don't want to imagine the scenario should the tank give way due to improper handling or maintenance. Since that is the optimun pressure that is required, you may/may not be able to get the desired outcome with a lesser pressure. And also, cooling a pc and cooling a tank with all its appliances switch on is 2 different platform altogether. One has a small reservoir to cool down while the other has a large volume of water as compared to the coolant reservoir on the pc.

[loupgarou]

I don't mind trying a peltier cooler myself. the ice probe chiller types (125 USD) is one of those. as are the hailea chiller (not sure cost) sold at keong seong and the teco microchiller.

heat sinks are fairly cheap (but maybe efficient ones aren't.. dunno).


I just don't know where to get the parts.

[BFG]

My second reply is from the link www.coolworksinc.com that you have provided.

Before you mentioned about this product, other hobbyist including me have wanted to use this 'gadget' for cooling our tank. But I found it hard to find a place to mount a few of this ice probe. Also, the ice probe has an ICEBANK system whereby ice would formed on the underside of this probe. I had seen this happen from 1 of the local pc mod forum. He had left 1 iceprobe in a glass/beaker overnite and in the morning a small amount of ice had formed. It needed more than 6 hr to achieve this in a small glass/ beaker of water. Imagine how long it would need to cool my 3ft tank. I had guessed that I need around 3 ice probe and 3 temperature controller. A resun chiller that I had saw for sale cost around $700++. How much does the total cost of the 3 iceprobe and 3 of the temp controller set me back? This is why I've told you that you cannot compare the chiller to the iceprobe. It is easy to connect a chiller to the tank but it was very hard for me to find an adequate space to mount 3 iceprobe.

So, my reply is not a form of 'rockthrowing'. You brought this idea into this forum to be discussed and I had provided the necessary answer based on my own personal experience. I had also posted a similar topic using iceprobe at www.petfrd.com and was told that that idea is impractical. I agree with the reply there so I am sharing information with you to prevent you from buying unnecessary item for this hobby. If you treat this as an enemy firing at you, well I can't say anymore. Go to www.petfrd.com to check on my query. In the future, please add (BFG please do not participate in this discussion) for every query or any ideas that you bring to this forum for discussion. I hadn't intend for you to get pissed at my comment and my comment was not meant to undermine anyone. Good luck in pursuing this hobby.

[crandf]

Calm down, I was referring to different things than what you said. I didn't want to specify things to avoid too much bad blood, but now the situation seemed to have worsened.

Firstly, it was loupgarou saying that 7.2 bar of air being blown directly at the water. 2ndly it was your reply stating fans, refridgerant and compressor, whereas I was talking about peltier elements wattage needed for peltier elements using the website as a guide.

(BTW: Cooking breakfast was a joke; high airpressure may be excessive, thus speculation about airpumps; CO2 tanks also hold compressed CO2; although vol of PC and aquariums are different, temperature to reduce also different.)

Anyway, I'm heeding tawauboy's suggestion to start the peltier discussion on a new thread. I will no longer be replying to this thread unless it is specific to vortex tubes.